Make sure your network router is allowing the IPSec ports through (UDP:500 and UDP:4500) or be sure to enable VPN pass-through if the router supports this option. Bypass the router is possible to make sure it is not causing the problem. Make sure your ISP is not blocking VPN ports, some providers will block the VPN ports on their end.
Solved: Client VPN Firewall Ports - The Meraki Community Hey All, I won't feel bad if you flame me with a RTFM, but does anyone know off hand which ports one would have to open on a firewall sitting in front of a Hub MX to let Meraki ClientVPN traffic (L2TP/IPSEC) through to said Hub? UDP 500, UDP 4500, ESP 50, AH 51? anything else, or not one of t Microsoft Always On VPN – Kemp Support May 07, 2020
I have recently changed to using BT, from EE, and am trying to set up the 'BT Business Smart Hub' for use with VPN. My setup (which previously worked fine with the EE router), was to set up port forwarding rules for UDP 1701, 500 and 4500 to forward to the same ports on my Synology NAS, for use with it's L2TP/IPSec VPN server, and use DDNS to allow the router's IP to be found from anywhere.
Oct 26, 2017 How to open a udp port in windows 10 - Microsoft Community Jun 14, 2018
Troubleshoot Mobile VPN with IKEv2
SonicWall IKE VPN negotiations, UDP Ports and NAT-Traversal explanation. 12/20/2019 1201 34134. DESCRIPTION: SonicWall IKE VPN negotiations, UDP Ports and NAT-Traversal explanation. RESOLUTION: Traffic on UDP port 500 is used for the start of all IKE negotiations between VPN peers. This is true of all IPSec platforms. In some cases, UDP port Solved: Setting up VPN - BT Community I have recently changed to using BT, from EE, and am trying to set up the 'BT Business Smart Hub' for use with VPN. My setup (which previously worked fine with the EE router), was to set up port forwarding rules for UDP 1701, 500 and 4500 to forward to the same ports on my Synology NAS, for use with it's L2TP/IPSec VPN server, and use DDNS to allow the router's IP to be found from anywhere.